Patent US2713753A successfully refreshed from Google Patents.
Patent US4055493A successfully refreshed from Google Patents.
US4055493A
Expired / Lapsed
US
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Method for opening a high-density packed column in liquid chromatography
Assignee: Japan Exlan Co Ltd
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Filing: 1976-11-29
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Granted: 1977-10-25
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Expires: 1996-11-29
Abstract
Abstract Method for opening a high-density packed column in liquid chromatography wherein a large number of components in a solution are separated by means of a column in which a swollen gel is packed at a high density. The improvement involves passing air through the column while heating the column to a temperature above at least 40° C. to shrink the volume of the packed column, and then opening the column. According to this process, there is no loss in the expensive gel nor contamination thereof and yet it's operating efficiency is greatly improved.
Inventors
- 👤 Shigeru Sawanishi
- 👤 Masahiko Ozaki
- 👤 Kikuji Katagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:26
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/291; B01D; B01D15/00; B01D15/08; B01D15/10; B01D15/20; G; G01; G01N; G01N30/00; G01N30/02; G01N30/50; B01J2220/00; B01J2220/50; B01J2220/54
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
70 words
A method for opening a high-density packed column in liquid chromatography wherein a large number of components in a solution are separated by means of a column in which a swollen gel is packed at a high density, characterized by passing air through the column while heating the column to a temperature above at least 40° C. to shrink the volume of the packed column, and then opening the column.
Claim 2
Independent Claim
70 words
A method for opening a high-density packed column in liquid chromatography wherein a large number of components in a solution are separated by means of a column in which a swollen gel is packed at a high density, characterized by passing air through the column while heating the column to a temperature above at least 40° C. to shrink the volume of the packed column, and then opening the column.
Claim 3
Dependent Claim
28 words
A method as claimed in claim 1 wherein the density of the swollen gel in the column is maintained at a vacant space ratio of less than 40%.
Claim 4
Dependent Claim
28 words
A method as claimed in claim 1 wherein the density of the swollen gel in the column is maintained at a vacant space ratio of 20 - 35%.
Claim 5
Dependent Claim
16 words
A method as claimed in claim 1 wherein the column heating temperature is 60°- 100° C.
Claim 6
Dependent Claim
27 words
A method as claimed in claim 1 wherein the dry air to be passed through the column is that having a relative humidity of less than 100%.
Claim 7
Dependent Claim
25 words
A method as claimed in claim 1 wherein the dry air to be passed through the column is that having a relative humidity below 80%.
Claim 8
Dependent Claim
25 words
A method as claimed in claim 1 wherein the dry air to be passed through the column is that having a relative humidity below 50%.
Claim 9
Dependent Claim
21 words
A method as claimed in claim 1 wherein the dry air is passed from the top of the column toward bottom.
Claim 10
Dependent Claim
29 words
A method as claimed in claim 1 wherein the flow rate of the dry air is 0.005 - 1.5 l/cm 2 .min. per unit cross-sectional area of the column.
Claim 11
Dependent Claim
29 words
A method as claimed in claim 1 wherein the flow rate of the dry air is 0.01 - 1.0 l/cm 2 .min. per unit cross-sectional area of the column.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-24 | 1981-04-25 | 1981-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-24 | 1985-04-25 | 1985-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-24 | 1989-04-25 | 1989-10-25 | $7700.00 | Window Closed / Lapsed |